Project Abstract Community college students are an underserved and at-risk population in terms of sexual and relationship health. Older adolescents/young adults consume a plethora of media messages, and many media messages about sex and relationships are inaccurate and unhealthy. Consumption of unhealthy media messages (e.g., those that normalize or glamorize risky sex) is related to risky sexual behaviors. Media literacy education (MLE), which aims to enhance critical thinking about media messages, is a novel and effective approach to relationship and sexual health promotion. A recent evaluation of a MLE program for older adolescents, Media Aware Sexual Health for Young Adults (MASH-YA), found that the program resulted in favorable short-term effects on community college students? (ages 18-19) sexual and relationship beliefs and behaviors, including a reduction in risky sexual behaviors. While evidence supports the effectiveness of MLE, there are no studies that have attempted to isolate its effects (i.e., enhancing critical thinking about media messages) on health outcomes, and little is understood about the mechanisms underlying the relationship between MLE and sexual health outcomes or the trajectory of MLE effects on sexual and relationship health over time. There are also gaps in our understanding of the challenges surrounding the effective implementation of sexual health programming at community colleges. Thus, this project proposes conducting a three-arm randomized control trial with older adolescents (i.e., ages 18-19) attending community college (N=1680). Community college campuses will be randomized to either the: (1) intervention group (i.e., MASH-YA); (2) active control group (i.e., sexual health programming from MASH-YA without MLE content); or, (3) no-treatment control group. Students will complete online questionnaires at pretest, posttest, 6m, and 12m follow-ups. The aims of this project are to evaluate the incremental effects of MLE on primary and secondary sexual and relationship health outcomes, compare the mechanisms underlying MASH-YA?s effects on health outcomes to the mechanisms underlying the effects of the active control program, and evaluate the long-term efficacy of MASH-YA on proximal and distal outcomes compared to an active control and no-treatment control. To assess challenges faced by community colleges in implementing evidence-based sexual health programming and gather information to inform strategies to enhance and support program implementation, community college personnel (N=60) will be asked to review the MASH-YA program and complete a questionnaire and structured interview to provide feedback on the program content and implementation. MLE is an effective approach to sexual and relationship health promotion with the potential to reduce health disparities among community college students. The findings from this study could advance theory, inform the development of future MLE interventions, and provide a rigorous long-term evaluation of the first evidence-based MLE program for sexual and relationship health promotion for older adolescents.